/*
 * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */
package com.oracle.svm.core.deopt;

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import com.oracle.svm.core.meta.SubstrateObjectConstant;

import jdk.vm.ci.meta.JavaConstant;
import jdk.vm.ci.meta.SpeculationLog;

public class SubstrateSpeculationLog implements SpeculationLog {

    private final ConcurrentMap<SpeculationReason, Boolean> failedSpeculations = new ConcurrentHashMap<>();

    public void addFailedSpeculation(SpeculationReason speculation) {
        failedSpeculations.put(speculation, Boolean.TRUE);
    }

    @Override
    public void collectFailedSpeculations() {
        // Nothing to do.
    }

    @Override
    public boolean maySpeculate(SpeculationReason reason) {
        return !failedSpeculations.containsKey(reason);
    }

    @Override
    public JavaConstant speculate(SpeculationReason reason) {
        if (!maySpeculate(reason)) {
            throw new IllegalArgumentException("Cannot make speculation with reason " + reason + " as it is known to fail");
        }
        return SubstrateObjectConstant.forObject(reason);
    }

    @Override
    public boolean hasSpeculations() {
        return true;
    }
}
